The Index #645 drawbar is 1/2" bar stock. The "wrenching" end is milled
to a 3/8" square, below that is a brazed on shoulder of approx. 5/8"
diameter X 5/16" thick. The drawbar drops through the spindle and seats
on a brass thrust bearing then the nut screws onto the end of the
spindle. These are OEM parts that I bought from Wells-Index.
I've made a couple of drawbars, using 1/2" drill rod, since I got the
OEM part...one for an end mill holder that has 3/8" threads in the shank
and another for a set of import collets that seem a bit undersize. The
collets go farther into the spindle taper and the OEM drawbar would
bottom out before tightening.

Rex the Wrench



Marty Escarcega wrote:
Rex the Wrench wrote in
:


With the top nut installed on the spindle, loosening the drawbar
causes the shoulder on the drawbar to come up hard against the nut
which forces the collet or tool holder to unseat from the spindle. My
#645 Index (#9 B&S taper) and my Bridgeport "M" head (#7 B&S taper)
are both set up in a similar fashion.

Rex the Wrench


Rex, is the drawbar something more than a common drawbar?
Must be?